Count of a particular value is different in dicover and in visulisation specially in line chart

I'm using split processor that separate on the basis of "/' (light/moon) and create a new field that is a basically simple values like "sun" and arrays like [light, bulb, sun] type

now the problem is lets suppose the field has two value
light
[moon,light]

now if I look and filter for "light" in discover section the hit is 2 which what i wanted , but at the same time if i look at the line chart of this in visualization the count is 3, i just want the count of light that is 2, how can I do this